(1) Field of the Invention
This invention relates to the improvements in the engine throttling of vehicles, particularly motorcycle, snowmobiles, and all terrain vehicles which are steered using handlebars and whose engine output is regulated by a thumb throttle control.
(2) Description of Related Art
Thumb throttles controls are standard equipment on nearly all snowmobiles and the majority of all terrain vehicles. Thumb throttle controls currently in use capture the motion of the thumb moving towards the handle bar which limits the ability of an operator to grip the handlebar or perform other functions with their hand while operating the thumb throttle controller. The advantage of this design is that the thumb is being pulled towards lever by the whole hand so the operator can overcome the resistance of a strong throttle return spring deal well with the fatigue induced by constantly having to resist the force of the throttle return spring. On vehicles equipped with sliding valve throttle bodies operator's hands receive additional fatigue trying to resist the movement of the sliding valve every time the vehicle is jostled around as it strikes any kind of bump. This phenomenon also reduces both vehicle control and forces the use of overly heavy return springs to reduce the tendency of the throttle blade to be bounced open.
U.S. Pat. No. 7,086,379 details the use of an secondary electronically controlled throttle body to improve the performance of a motorcycle equipped with a traditional twist grip throttle controller coupled directly to the primary throttle body by a traditional wire cable.
U.S. Pat. No. 7,010,955 describes the use of a throttle by wire throttle control setup on a motorcycle using data taken from a rotating handlebar grip. No mention is made of the use of any kind of sliding or hinging throttling member.
U.S. Pat. Nos. 6,889,654 and 6,699,085 describe how data taken from a finger actuated lever on the handlebar of a personal watercraft can be used to control the throttling of the watercraft's engine. Mention is made of using this throttling device on other vehicles. The throttle control device cited in the patent is unlike my thumb throttle device in that it consists of a lever mounted in front of the handlebar. The lever is pulled toward the handlebar by the index finger. No mention is made of a throttle control using a sliding member or of a thumb throttle control. The advantage of such a system is cited as being the ability to reduce the amount of return spring necessary to move the throttling lever to its rest position. No mention is made of reducing rider fatigue by decoupling the throttle control lever from the reciprocating mass in the engine's throttle body.
U.S. Pat. No. 5,775,167 describes the use of an additional throttle lever in conjunction with a traditional thumb throttle. This additional throttle is actuated by the index finger in a manner similar to the throttles employed on some personal watercraft and depicted in U.S. Pat. Nos. 6,889,654 and 6,699,085. No mention is made of improving thumb throttle performance using any of the techniques detailed in my claims.
U.S. Pat. No. 6,658,965 details the design of a thumb actuated throttle which rotates around the handlebar mimicking the motion of a traditional twist grip throttle controller.
U.S. Pat. No. 4,899,610 details the use of a thumb throttle, which pivots about two points so that rider fatigue is reduced by altering the mechanical advantage of the mechanism at different throttle openings. The disadvantage of this approach is a loss of throttle control.